Frost dates by ZIP code: The nearest NOAA stations to your ZIP, 1991-2020 normals
Enter a five-digit ZIP code. PlainClimate finds its center (Census Bureau 2024) and the five nearest NOAA stations with frost dates, and shows each station's last spring and first autumn 32°F dates with its distance and elevation.
Frost dates near ZIP 46806
The USDA's 2023 Plant Hardiness Zone Map puts ZIP 46806 in zone 6a (the coldest night of a typical year: -10 to -5°F).
The nearest station, Fort Wayne, IN, is 8 miles from the ZIP's center: its last spring frost comes after April 24 in half of years and after May 10 in one year in ten. By the USDA's method its plant hardiness zone is 6a.
| Station | Distance | Elevation | Last frost (median) | 1 in 10 after | First frost (median) | Hardiness zone |
|---|---|---|---|---|---|---|
| Fort Wayne, INFort Wayne International Airport | 8 mi | 791 ft | April 24 | May 10 | October 21 | 6a |
| Woodburn, IN3 mi N | 15 mi | 710 ft | April 27 | May 11 | October 19 | – |
| Decatur, IN1 mi N | 16 mi | 785 ft | April 23 | May 8 | October 19 | 6a |
| Bluffton, IN6 mi N | 16 mi | 861 ft | April 24 | May 9 | October 20 | 6a |
| Garrett (1 mi S), IN | 20 mi | 870 ft | May 2 | May 16 | October 10 | – |
Frost comes later in spring at higher and colder stations and earlier in low, open ground: prefer a station at a similar elevation to yours. Hardiness zone in the table: the USDA's rule (the average of each year's coldest night, 1991-2020) applied to the station's own record.
Every frost threshold at Fort Wayne
NOAA publishes the dates for several temperatures and odds. A 30% spring date means a 3-in-10 chance of a later frost (the convention almanacs use); 50% is the median; 10% the cautious date.
| Threshold | Spring, 10% | Spring, 30% | Spring, 50% | Spring, 90% | Autumn, 50% | Autumn, 10% |
|---|---|---|---|---|---|---|
| 36°F (light frost) | May 18 | May 10 | May 4 | April 20 | October 9 | September 25 |
| 32°F | May 10 | May 1 | April 24 | April 10 | October 21 | October 8 |
| 28°F (hard freeze) | April 28 | April 18 | April 12 | March 28 | November 1 | October 19 |
| 24°F | April 15 | April 6 | March 31 | March 16 | November 12 | November 1 |
Source: NOAA NCEI 1991-2020 annual normals; ZIP centers: Census Bureau 2024 Gazetteer; USDA 2023 Plant Hardiness Zone Map, ZIP listings: PRISM Group, Oregon State University, https://prism.oregonstate.edu, accessed October 8, 2026. Autumn 10%: one year in ten has its first frost before this date.